In infinitely variable change-speed gears, according to the state of the art, the selector valve is generally arranged separately from the hydraulic control unit, which is arranged in the oil pan in a separate selector valve housing in the upper region of the transmission. The connection between the hydraulic control unit and the selector valve housing, as well as between the selector valve housing and the forward clutch and the backward brake, is established by pipes. When the transmission is shut off, oil can disadvantageously leak from the connecting pipe between the selector valve and the forward clutch, because in the parking position P, the upper end of the line is open via a bleed valve and on the lower end, oil can escape into the primary shaft via a rectangular ring and a bleed bore arranged behind it. The amount of air, which reaches the line due to this process and is pushed into the clutch when engaging a gear for the first time after starting, fluctuates drastically and, therefore, has a negative effect on the shifting comfort and the shift adaptation.
It is the object of the present invention to create a device, which prevents oil from escaping from an end comprising a bleed valve of a connecting pipe containing fluid, especially hydraulic fluid, particularly of the connecting pipe between the selector valve and the clutch to the front in an infinitely variable change-speed gear.